When talking about a child’s height, you have to keep in mind that pesky gene pool. At least once a week, I have a parent in my office who wants me to do sophisticated testing because their child is shorter than his playmates. When I ask the five-foot-one mother about the rest of the family, I find out that the father is five-foot-five and both sets of grandparents are under five-foot-three. With that kind of genetic background, the chances of giving birth to a future Shaquille O’Neal are pretty slim.
Just like adults, children exhibit different growth patterns. In our culture, it’s not that unusual to find men six-foot-six or five-foot-five. At either height they’re considered healthy and normal. We can accept the same variation in children.
The rule of thumb is that after the first year of life, youngsters grow about two inches a year throughout childhood. Between ages three and six, they grow an average of two to three inches a year. If your child is following these guidelines, very few pediatricians will recommend blood tests.
If your child has short parents, he will probably be a short adult. If your child has tall parents, he will probably by a tall adult. And if he has one tall and one short parent, he will probably fall somewhere in the middle. The formula we use to estimate the height of a full grown child is to take the parents’ height in inches and apply the Rule of Five. For easy explanation, let’s look at a situation where a child has a five-foot-three mother (63 inches) and a six foot father (72 inches). Here’s how the formula works.
Assuming the child is a son, we’ll take the father’s height (72 inches) and add the mother’s height plus five inches (68 inches). Then we add them together (140 inches), and divide by two (70 inches). The boy will be about five-foot-ten as an adult male.
The average female is shorter than the male. So for a daughter, take the father’s height (72 inches) minus five inches (67 inches). Add the mother’s height (63 inches). The result is 130 inches, divided by two (65 inches). The girl will probably be five-foot-five when she’s fully grown.
Unless there’s a serious pituitary imbalance or other rare condition causing highly abnormal growth spurts or delays, there’s nothing to do but watch your children grow at their own pace. Let me reassure you that height or lack of it isn’t that important if the child is happy and brimming with good health.